Medical device with textured surface

ABSTRACT

Described is a guide catheter for guiding other medical devices into or through a body lumen, comprising: a polymeric, tubular inner liner having a textured inner surface; and, a polymeric jacket bonded to an exterior of the inner liner; wherein the texture of the inner surface of the inner liner reduces the coefficient of friction between the inner liner and the other medical devices.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Provisional Application No.61/683,087, filed Aug. 14, 2012, which is herein incorporated byreference in its entirety.

TECHNICAL FIELD

The present invention relates to medical devices. More particularly, thepresent invention relates to adding surface texture to a component of amedical device in order to improve device longevity and performance.

BACKGROUND

The implantation of medical devices has become a relatively commontechnique for treating a variety of medical or disease conditions withina patient's body. Depending upon the conditions being treated, today'smedical implants can be positioned within specific portions of apatient's body where they can provide beneficial functions for periodsof time ranging from days to years. Methods to reduce or prevent fatigueof such devices while implanted are desired.

SUMMARY

Example 1 is a guide catheter for guiding a medical device into orthrough a body lumen. The guide catheter comprises a polymeric, tubularliner and a polymeric jacket. The tubular liner has a textured innersurface, the tubular liner defining a catheter lumen. The polymericjacket is bonded to an exterior of the liner. The textured inner surfaceof the tubular liner is defined by a plurality of protrusions disposedabout and extending radially inward with respect to a longitudinal axisof the tubular liner.

In Example 2, the guide catheter of Example 1, wherein the protrusionsare shaped to minimize contact area and frictional resistance betweenthe textured inner surface of the tubular liner and the medical devicewhen the medical devices disposed within the catheter lumen.

In Example 3, the guide catheter of Example 2, wherein the protrusionsextend longitudinally along the tubular liner.

In Example 4, the guide catheter of Examples 2 or 3, wherein theprotrusions extend in a helical pattern longitudinally along the tubularliner.

In Example 5, the guide catheter of any of Examples 1-4, wherein thetubular liner comprises an extruded tubular member formed of a polymericmaterial.

In Example 6, the guide catheter of any of Examples 1-5, wherein thetubular liner comprises a molded tubular member formed of a polymericmaterial.

Example 7 is a medical system comprising an elongate medical device anda catheter. The elongate medical device includes an outer surface. Thecatheter has a lumen sized to receive the elongate medical device, thelumen including an inner surface. One of the outer surface of theelongate medical device and the inner surface of the guide catheterlumen is a textured surface, and the other of the outer surface of theelongate medical device and the inner surface of the guide catheterlumen is a substantially smooth surface. The textured surface isconfigured to minimize friction between the textured surface andsubstantially smooth surface when the elongate medical device and thecatheter are moved relative to one another when the elongate medicaldevice is disposed within the catheter lumen.

In Example 8, the medical system of Example 7, wherein the texturedsurface includes a plurality of raised surface features.

In Example 9, the medical system of Examples 7 or 8, wherein theplurality of raised surface features extend longitudinally along thetextured surface.

In Example 10, the medical system of any of Examples 7-9, wherein theplurality of raised surface features extend in a helical patternlongitudinally along the textured surface.

In Example 11, the medical system of any of Examples 7-10, wherein theelongate medical device comprises an extruded tubular member formed of apolymeric material.

In Example 12, the medical system of any of Examples 7-10, wherein theelongate medical device comprises a molded tubular member formed of apolymeric material.

In Example 13, the medical system of any of Examples 7-10, wherein theelongate medical device is a guide wire.

Example 14 is a method of forming a guide catheter for guiding a medicaldevice into or through a body lumen. The method comprises forming aguide catheter shaft including an inner lumen sized to receive themedical device therein, the inner lumen including a textured innersurface along at least a portion of a longitudinal length of thecatheter shaft. The textured inner surface is configured to minimizefriction between the textured inner surface and the medical device whenthe medical devices disposed within the catheter lumen.

In Example 15, the method of Example 14, wherein forming the guidecatheter shaft includes forming an liner having a surface texture on aninner surface thereof, and disposing an outer jacket over the liner,wherein the inner surface of the liner defines the textured innersurface of the inner lumen of the catheter shaft.

In Example 16, the method of Example 15, wherein forming the linerincludes extruding a tubular polymeric member over an extrusion corehaving a surface configured to form the surface texture on the innersurface of the liner.

In Example 17, the method of Example 14, wherein forming the guidecatheter shaft includes providing a polymeric jacket, extruding an linerover an extrusion core having a surface configured to form a texture onan inner surface of the liner, bonding the polymeric jacket to anexterior of the liner, and removing the extrusion core, whereupon suchremoval the inner surface of the liner defines the textured innersurface of the inner lumen of the catheter shaft.

In Example 18. the method of any of Examples 14-17, wherein the texturedinner surface includes a plurality of raised surface features.

In Example 19, the method of any of Examples 14-18, wherein theplurality of raised surface features extend longitudinally along theliner.

In Example 20, the method of any of Examples 14-19, wherein theplurality of raised surface features extend in a helical patternlongitudinally along the liner.

While multiple embodiments are disclosed, still other embodiments of thepresent invention will become apparent to those skilled in the art fromthe following detailed description, which shows and describesillustrative embodiments of the invention. Accordingly, the drawings anddetailed description are to be regarded as illustrative in nature andnot restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of heart with a lead system implantedaccording to one embodiment.

FIG. 2 is a perspective view of a lead of the lead system of FIG. 1according to one embodiment.

FIG. 3 is a cross-sectional view of the lead of FIG. 2.

FIG. 4 is a cross-sectional view of a conductor including an insulativelayer for use in the lead of FIG. 2, according to one embodiment.

FIG. 5 is a cross-sectional view of a conductor including an insulativelayer for use in the lead of FIG. 2, according to another embodiment.

FIG. 6 is cross-sectional view of a lead body of the lead of FIG. 2,including an enlarged portion A illustrating surface features on aninternal surface of a lead body lumen.

FIG. 7 is a cross-sectional view of a core or mandrel for use in forminga texture on the inside surface of a tubular medical device according toone embodiment.

FIG. 8 is a cross-sectional view of a portion of an exemplary tubularmedical device component showing a surface texture on an inside surfaceaccording to another embodiment.

FIGS. 9A-9H are cross-sectional elevation views of exemplary textureprotrusion profiles according to various embodiments.

FIG. 10 is a side view of a guide catheter that can include a texturedinner surface according to one embodiment.

FIG. 11 is a side view of an exemplary balloon dilation catheter havinga textured external surface according to one embodiment.

FIG. 12 is a side view of an exemplary monorail balloon dilatationcatheter having a textured external surface according to one embodiment.

While the invention is amenable to various modifications and alternativeforms, specific embodiments have been shown by way of example in thedrawings and are described in detail below. The invention, however, isnot limited to the particular embodiments described. On the contrary,the invention is intended to cover all modifications, equivalents, andalternatives falling within the scope of the invention as defined by theappended claims.

DETAILED DESCRIPTION

FIG. 1 is a schematic view of a cardiac rhythm management system 10including an implantable medical device (IMD) 12 and an implantablemedical lead 14 in an implanted position with respect to a patient'sheart 20 according to one embodiment. As shown, the IMD 12 can include apulse generator such as a pacemaker, a cardioverter/defibrillator, acardiac resynchronization therapy (CRT) device, or a CRT device withdefibrillation capabilities (a CRT-D device), among other appropriateIMDs 12. In the illustrated embodiment, the IMD 12 can be a CRT or CRT-Ddevice. In various embodiments, the IMD 12 can be implantedsubcutaneously within the body, for example, at a location such as inthe patient's chest or abdomen, although other implantation locationsare possible.

The lead 14 is a flexible, elongate structure and, as shown in FIG. 1,includes a proximal end 16 and a distal end 18. In the illustratedembodiment, the proximal end 16 is coupled to or formed integrally withthe IMD 12, and the distal end 18 of the lead 14, in turn, is implantedin a coronary vein adjacent to the left ventricle of the heart 20 so asto facilitate stimulation of the left ventricle. In various embodiments,additional leads (not shown in FIG. 1) can be implanted in or adjacentto other regions of the heart 20, e.g., the right atrium or rightventricle, or on the epicardial surface of the heart 20, based on theparticular clinical needs of the patient. While not shown in FIG. 1, asexplained in greater detail herein, the lead 14 includes one or moreelectrodes and one or more conductors coupled to each electrode toelectrically couple the electrode with the IMD 12 for sensing intrinsiccardiac activity and providing electrical stimuli to the cardiac tissue.

FIGS. 2 and 3 are perspective and cross-sectional views, respectively,of a portion of the lead 14. As shown, the lead 14 includes a lead body36 and an exemplary arrangement of first, second and third conductorassemblies 38, 40, 42 extending there through. In various embodiments,the lead body 36 is a flexible tubular body that defines a coilconductor lumen 44 and two wire conductor lumens 46, 48 extendingbetween the proximal and distal ends 16, 18 of the lead 14 (see FIG. 1).As further shown, the first, second and third conductors 38, 40, 42extend, respectively, through the first, second and third lumens, 44,46, 48. In various embodiments, each of the lumens 44, 46, 48 has, inthe various embodiments, an inner surface that is substantially smooth.In various embodiments, the aforementioned substantially smooth innersurfaces each have a roughness average (Ra) of less than 10 microinches.

Additionally, while the particular lead 14 illustrated includes three(3) lumen/conductor assembly combinations, in various other embodimentsthe lead 14 can include either more or fewer lumens and conductors,depending on the type of the IMD and the clinical needs of the patient.

The lead body 36 can be made from a flexible, biocompatible materialsuitable for lead construction. In various embodiments, the lead body 36is made from a flexible, electrically insulative material. In oneembodiment, the lead body 36 can be made from silicone rubber. Inanother embodiment, the lead body 36 can be made from polyurethane. Invarious embodiments, respective segments of the lead body can be madefrom different materials, so as to tailor the lead body characteristicsto its intended clinical and operating environments.

In the various embodiments, the conductors of the lead 14 can be lowvoltage or high voltage conductors. As used herein, “low voltage”conductors generally refer to conductors that are configured forlow-voltage functions, such as sensing and pacing. “High voltage”conductors refer to conductors that are configured to conduct current athigh voltages, as is required during defibrillation therapy, forexample. The conductors can be cable conductors or coiled conductors. Acoiled conductor is generally helical in configuration and includes oneor more conductive wires or filaments. A cable conductor has asubstantially linear configuration and can also include a plurality ofconductive wires or filaments.

As shown in FIGS. 2 and 3, the conductor assembly 38 includes aconductor member 50 and an outer insulative layer 52 disposed about theconductor member 50. In the illustrated embodiment, the conductor member50 is a low voltage conductor coil and can be part of a systemconfigured to provide pacing or CRT stimuli and/or to sense intrinsiccardiac electrical activity. Thus, in the various embodiments, theconductor member 50 can be coupled to a low voltage electrode (notshown) for facilitating the aforementioned stimulation and sensingfunctions.

As further shown, the conductor assemblies 40, 42 include, respectively,conductor members 54, 56, which in turn, respectively, have outerinsulative layer 58, 60 disposed thereabout. As shown in the embodimentillustrated in FIG. 2, the conductor members 40, 42 can comprise asingle wire. Alternatively, as shown in the embodiment of FIG. 3, theconductor members 54, 56 can be in the form of multi-strand cableconductors including, respectively, a plurality of wires 54A, 56A. Theconductor members 54, 56 can, in various embodiments, be configured forhigh voltage applications such as antitachyarrhythmia therapy orcardioverter/defibrillator therapy systems, in which case they wouldeach be coupled to at least one relatively large defibrillation coilelectrode. Alternatively, the conductor members 54, 56 can also be usedin low voltage applications similar to those described previously withrespect to the conductor member 50. In the various embodiments, theconductor members 50, 54 and/or 56 can be made of a suitableelectrically conductive material such as Elgiloy, MP35N, tungsten,tantalum, iridium, platinum, titanium, palladium, stainless steel, aswell as alloys of these materials.

In the various embodiments, the outer insulative layers 52, 58, 60 areconfigured to have, respectively, textured external surfaces 62, 64 and66. As shown, the textured external surfaces 62, 64 and 66 are disposedopposite the respective conductive member, and can contact thesubstantially smooth inner surface of the conductor lumen in which theparticular conductor assembly is disposed.

FIGS. 2 and 3 illustrate, schematically, an exemplary external surfacetexture that takes the form of a series of raised elongate structures,which are roughly parallel to the longitudinal axis of the conductors38, 40, 42. In various embodiments, other types of surface textureconfigurations can be utilized on the textured external surfaces of theouter insulative layers 52, 58, 60. For example, the insulative layers52, 58, 60 can include surface texture typified by distinct, raisedfeatures on the outer surface of the insulative layer of a conductor.The surface texture can be uniform or non-uniform. Surface texture can,but need not, have a directionality associated with either or both thelongitudinal axis of the material or the axis perpendicular thereto, andcan include micron scale ridges, micronodules or raised features, forexample, of any kind, rounded, flat-topped, or angular.

Adding surface texture or roughness to form the textured externalsurfaces 62, 64 and 66 results in these surfaces having differentsurface characteristics, in particular, different surface roughnesses,than the substantially smooth inner surface of the respective conductorlumen in which the particular conductor assembly is disposed. Thisdifferential surface roughness has been found to minimize frictionalforces between these respective surfaces when they contact one another.

The presence of the texture on the textured external surfaces of theconductor assembly outer insulative layers, and the correspondingreduction in frictional resistance with respect to the adjacent innersurface of the conductor lumen, can also increase the manufacturabilityand ease of assembly of the lead assemblies. During the manufacture oflead assemblies, certain processing aids (e.g., vacuum, alcohol or othersolvents, pressurized gases) are generally used in order to string onecomponent co-radially through another, such as a cable conductor througha conductor lumen. The use of such processing aids may betime-consuming, costly and ineffective at reducing friction. Therefore,eliminating the need for such processing aids by reducing the frictionbetween components during assembly of the medical devices or systems canbe beneficial.

The specific configuration of the surface texture on the texturedexternal surfaces 62, 64 and 66 can be based upon factors such as,without limitation, the types and sizes of the conductor members and theconductor lumens, the proximity of (e.g., clearance between) thetextured external surfaces of the conductor assemblies to the innersurfaces of the conductor lumens, and other lead design andmanufacturing considerations. In one exemplary embodiment that has beenfound to exhibit minimal frictional resistance between the conductorassemblies and the corresponding conductor lumen inner surfaces, thesubstantially smooth inner surface of the conductor lumen can have aroughness average (Ra) of less than 10 microinches, and the averagesurface texture roughness on the textured external surface of the outerinsulative layer of the corresponding conductor assembly can be greaterthan about 16 microinches.

In various embodiments, the outer insulative layers can include or beformed from insulative materials such as, for example, ethylenetetrafluoroethylene (ETFE), polytetrafluoroethylene (PTFE), expandedPTFE (ePTFE), fluorinated ethylene propylene (FEP), perfluoro-alkoxy(PFA), polyvinylidene fluoride (PVDF), polyether ether ketone (PEEK),polyethylene terephthalate (PETE), silicone, and copolymers of theforegoing. In various embodiments, the outer insulative layers 52, 58,60 can be extruded or molded onto the conductor members 38, 40, 42, orcan be extruded or molded separately from the conductor members 38, 40,42 which can then be strung within the extruded or molded insulativelayers 52, 58, 60. The textured external surfaces 62, 64, 66 can begenerated by extrusion dies that are machined to form the desiredtexture during the extrusion process. Alternatively, a mold can betexturized (e.g., by roughening the inner surface of the mold) and theresulting texture can then be transferred to the insulation layer duringa molding process.

In another alternative embodiment, a smooth outer insulative layer maybe extruded, coated or molded onto the conductor and subsequentlyaltered, treated or roughened in order to provide texture to the layer.For example, an extruded or molded lead assembly component can undergoan embossing step after being produced. The embossing step can includeapplying the surface of the extruded lead component to a spiked rollerin order to result in raised and lowered areas on the surface of theextruded or molded polymer. Another alternative step to introducetexture to an extruded or molded polymer surface can be to pass theextruded or molded polymeric component, before the component hassolidified, through a die in order to include surface texture orroughness.

Another alternative subsequent method to extrusion or molding in orderto introduce texture can be a grit-blasting process to create raised andlowered areas on a surface of an extruded or molded polymer. The gritmaterial can be a sublimating material, such as frozen carbon dioxideparticles, for example, in order to eliminate contamination of thesurface of the extruded or molded polymer with embedded grit material.In short, the particular processes and equipment utilized to form thetextured external surfaces of the outer insulative layers are notlimited to a particular process or equipment.

FIGS. 4 and 5 illustrate alternative cross-sectional views of insulatedcable conductor assemblies 140, 240, respectively, that may be includedin the lead 14 in lieu of or in addition to either of the conductorassemblies 40, 42 discussed herein. As shown, the conductor assemblies140, 240, respectively, have outer insulative layers 158, 258 withtextured external surfaces configured to minimize the interfacial areabetween the inner surfaces of the respective conductor lumens and theouter insulative layers 158, 258.

As shown in FIG. 4, the conductor assembly 140 includes a multi-strandcable conductor member having a plurality of wires 154A wound together.As further shown, the outer insulative layer 158 axially surrounds theconductor wires 154A and includes a textured external surface defined bya plurality of surface segments 170 arranged about the longitudinal axisof the conductor assembly 140, with ridges between adjacent surfacesegments 170. The configuration of the outer insulative layer 158 issuch that contact of the outer insulative layer 158 and thecorresponding inner surface of the conductor lumen in which theconductor assembly 140 is disposed will be substantially confined to theridges between adjacent surface segments 170, thus minimizing thecontact area between these elements, which in turn operates to minimizefrictional forces therebetween.

As shown in FIG. 5, the conductor assembly 240 includes a single wireconductor member 254, and the outer insulative layer 258 is disposedabout the conductor member 254 and includes a textured external surfacedefined by a plurality of surface segments 270 arranged about thelongitudinal axis of the conductor assembly 240, with ridges betweenadjacent surface segments 270. The configuration of the outer insulativelayer 258, and in particular the presence of the ridges between theadjacent surface segments 270, operates in substantially the same manneras the outer insulative layer 158 to minimize friction between the outerinsulative layer 258 and the inner surface of the lead body conductorlumen in which the conductor assembly 240 resides.

In the embodiments illustrated in FIGS. 4 and 5, the textured externalsurfaces of the outer insulative layers 158, 258 have, respectively,twelve (12) surface segments 170 and five (5) surface segments 270. Theparticular number of surface segments, however, can be varied within thescope of the various embodiments. Additionally, the cross-sectionalshape of the outer insulative layers 158, 258 can be varied from theflat surface segment configuration with generally V-shaped ridges shownin FIGS. 4 and 5. For example, in various embodiments, the ridgesbetween adjacent surface segments can be rounded or lobe-shaped. Invarious embodiments, the surface segments 170, 270 can have concave orconvex cross-sectional profiles.

The outer insulative layers 158, 258 can be produced by extrusion aboutthe respective conductor member 154, 254 using an extrusion dieincluding an inner diameter with a design that results in the pluralityof surface segments 170, 270. Alternatively, the outer insulative layers158, 258 can be formed via molding operations utilizing a mold thatincludes texture to result in surface texture of the lead being theplurality of surface segments 170, 270.

In the embodiments shown in FIGS. 2-5, the various conductor assembliesinclude outer insulative layers with textured external surfaces toreduce friction between the conductor assemblies and the lumens throughwhich the conductor assemblies extend. Alternatively, or additionally,the inner surfaces of the respective conductor lumens can be textured orroughened in order to reduce friction with the conductors, which canhave outer insulative layers that are substantially smooth (i.e., nottextured). For example, FIG. 6 shows a lead body 300 with 4 lumens 301,302, 303, 304. The enlarged area of detail A in FIG. 6 shows that theinner surface 315 of lumen 304 is textured. The other lumens 301, 302,303 can be similarly textured. The texture can reduce friction betweenthe corresponding conductor assembly and the inner surface of theconductor lumen 301, 302, 303, 304 in the same manner previouslydescribed with respect to embodiments in which the outer insulativelayer of the conductor assembly has a textured external surface and theinner surface of the conductor lumen is substantially smooth.

In the various embodiments, the texture on the inner surface of theconductor lumen 301, 302, 303, 304 can be formed during extrusion ormolding of the lead body 300. The die or mold (e.g., a core pin) usedfor extrusion or molding, respectively, can be configured with thedesired texture in order to result in an inverse texture being locatedon an inner surface of an extruded lumen. Alternatively, texture orroughening of the inner surfaces of the respective conductor lumens 301,302, 303, 304 can be applied after extrusion or molding of the lead body300.

While the embodiments illustrated in FIGS. 2-6 relate to implantablemedical leads, the principles of the present disclosure can also beapplied to other medical devices. For example, surface texture can beapplied to an inner liner or inner surface of a lumen of a guidecatheter in order to reduce surface friction between the inner surfaceof the guide catheter lumen and a lead or other medical device having asubstantially smooth outer surface designed to be delivered or guidedthrough the catheter. FIG. 7 shows an exemplary cross-section of a core400 that can be used to produce a tubular liner 500 having a texturedinner surface, an embodiment of which is shown in cross-section in FIG.8, that can be used in a tubular medical instrument such as, forexample, a catheter. In various embodiments, the core 400 can also beused to form the textured inner surfaces of the conductor lumens 301,302, 303, 304 of the lead body 300.

In various embodiments, the core 400 can be made of Acetal (DELRIN™) forexample, although other materials are possible. As shown, an exemplarytexture 405 is present on an outer surface 407 of the core 400. Asfurther shown in the enlarged area of detail B, the texture 405 caninclude indentations 410 sized and shaped as desired to provide atexture on the inner surface of the liner 500. The texture 405 can beapplied to a full or a partial length and a full or partial radialcircumference of the core 400.

In order to form the liner 500, a tubular piece of thermoplasticpolymer, for example, can be placed over the textured core 400 andheated to re-flow into the texture 405 of the core 400. In variousembodiments, the thermoplastic polymer may be a polyether block amidematerial, e.g., materials sold under the brand name PEBAX™, or apolyethylene material with a tie layer to PEBAX™, polyisobutylene basedpolyurethane (PIB-PU), or some other thermoplastic polymer. After theliner 500 is cooled and cured, the core 400 is pulled and removed fromwithin the liner 500. The resulting liner 500 has a texture profile thatis the inverse of the texture 405 on the core 400. In various otherembodiments, the catheter liner 500 can be extruded or molded over thecore 400.

As shown in FIG. 8, the liner 500 has an inner surface 510 with texture515, which is shown in greater detail in enlarged area of detail C. Onceformed, the liner 500 can be placed or strung within a tubular polymericjacket to form a guide catheter shaft. Alternatively, the liner 500 maybe covered by one or more segments of a polymeric material to form thecompleted guide catheter shaft. Still other techniques for forming acompleted guide catheter shaft including the liner 500 can be usedwithin the scope of the present disclosure.

The texture 515 on the liner 500 can reduce surface friction between theinner surface of the liner 500 and another device (e.g., a lead,catheter, guide wire, balloon angioplasty device, etc.) slidablydisposed therein. The reduction in the coefficient of friction resultsin less force being used to move the other device through the catheter,which can result in more precise use of the device by a user.

The configuration of the texture 515 can be varied and optimized for theparticular clinical use of the corresponding catheter. Various exemplarycross-sections of single extruded or molded texture profiles are shownschematically in FIGS. 9A-H. As shown, the various surface textures aredefined by a plurality of protrusions disposed about and extendingradially inward with respect to the longitudinal axis of the liner 500.In the various embodiments, the protrusions are shaped to minimizecontact area and frictional resistance between the textured innersurface of the corresponding catheter lumen and a medical device (e.g.,a guide wire, catheter, stimulation lead, and the like) disposed withinthe catheter lumen.

FIG. 9A shows a cross-section of a protrusion 600 having a generallyflat, upper surface 601. FIG. 9B shows a protrusion 602 having a singletriangular-shaped depression 603 along its length. FIG. 9C shows aprotrusion 604 with a rounded, convex-shaped upper surface 605. FIG. 9Dshows a protrusion 606 having a concave depression 607 along its length.FIG. 9E shows a protrusion 608 having a triangular-shaped extension 609.FIG. 9F shows a protrusion 610 that includes two concave curves alongthe length that result in the protrusion extending outward generally asa linear extension 611 along its longitudinal length. FIG. 9G shows aprotrusion 612 having two triangular-shaped extensions 613. FIG. 9Hshows a protrusion 614 with two triangular-shaped depressions 615. Othersuitable shapes of protrusions can be used, and are not limited to thoseshown.

In the various exemplary embodiments shown in FIGS. 9A-9H, the variousprotrusion profiles form, in effect, channels or reservoirs forreceiving a fluid, e.g., saline, that may be introduced into therespective catheter lumen as part of the medical procedure in which thecatheter is used. Relative motion of the catheter and the elongatemedical device (e.g., a guide wire, lead or other catheter) disposedwithin the lumen thereof can tend to cause the fluid to be drawn overand across the protrusions by hydrodynamic forces. This moving salinecreates a lubricating force that can tend to push the elongate medicaldevice away from the textured inner surface of the catheter, thusfurther minimizing friction between the respective surfaces.

In various embodiments, the particular texture can be molded or extrudedsuch that the texture extends generally longitudinally along thecomponent. Alternatively, the extruded or molded texture can extendhelically along or around the surface of the elongated component, e.g.,by rotating the core 400 or the extruded polymer component during theextrusion process.

FIG. 10 illustrates an exemplary guide catheter that can have texture onan inner luminal surface. Guide catheter 700 is tubular and has a hub732, a shaft 734, a proximal end 736 and a distal end 738. Texture (notvisible in FIG. 11) can be present on an inner surface of an inner lumen740 of the shaft 734. In one embodiment, the catheter shaft 734 includesthe liner 500 such that the inner surface of the inner lumen 740 has aninner surface texture to minimize friction between the inner surface andanother device disposed and movable within the catheter shaft 734. Inone embodiment, the catheter shaft 734 is a unitary structure includingthe textured inner surface described herein but without requiring theinclusion of the separate liner 500. In various embodiments, thetextured inner surface can extend along all or only one or more portionsof the length of the catheter shaft 734.

While the embodiments of FIGS. 7-10 relate to medical devices havingtextured internal surfaces, a surface texture configured to lower thecoefficient of friction between components can also be located on anouter surface of one or more components of a medical device system thatmay contact each other. For example, two or more components or devices(e.g., balloon catheters, leads, ablation devices, stents) may extendthrough a single guide or delivery catheter. One or more than one of thecomponents can include texture on an outer surface to reduce frictionbetween the components themselves and between the components and aninner luminal surface of the guide or delivery catheter.

An example of a system including components that may include suchtexture on an outer surface of one or more components is a dual ballooncatheter system, which may be deployed through a common guide catheter.In such embodiments, one or both of the balloon catheters may includetexture on at least a portion of their outer surface. FIG. 11illustrates an exemplary balloon dilatation catheter 880. The catheter880 has a main shaft section 882, an intermediate sleeve section 884 anda distal balloon section 886. The catheter 880 is adapted forover-the-wire applications, and as such is configured to be deployedusing a guidewire 890 slidably disposed within an inner lumen (notshown) of the catheter 880. The catheter 880 can include afriction-reducing texture 892, for example, as shown, on itsintermediate sleeve section 884, which section, in use, slidablycontacts a surface of another device and/or a guide catheter throughwhich the balloon dilatation catheter 880 is deployed. In variousembodiments, additional regions of the outer surface of the balloondilatation catheter 880 can include a friction-reducing surface texture.In various embodiments, the inner lumen (not shown) of the catheter 880can include a textured inner surface according to the variousembodiments described herein, which can result in minimizing frictionalforces between the textured inner surface of the catheter 880 and theguidewire 890 as the catheter 880 is deployed by an over-the-wiretechnique.

FIG. 12 illustrates a monorail balloon catheter 900 including anelongated catheter shaft 920 having proximal 928 and distal 926 ends,and a balloon 924. The balloon 924 is at the distal end portion 926 ofthe catheter 900. A guide wire 960 is shown introduced into guide wireport 940, and can extend out the distal end of the catheter 900. Invarious embodiments, the monorail balloon catheter 900 can be deployedalone, or in combination with another balloon catheter (e.g., theballoon dilatation catheter 880 discussed herein) within a common guidecatheter. Accordingly, in various embodiments, a texture 942 can bepresent on the shaft 920 at or near the distal end portion 926 tominimize friction between the balloon catheter 900 and other adjacentsurfaces in which the shaft 920 may come into sliding contact duringdeployment, according to the various embodiments described herein. Invarious embodiments, the surface texture 942 operates to reduce frictionbetween the textured outer surface of the shaft 920 and the outersurface of the guide wire 960 proximate the guide wire port 940.

It will be readily appreciated, based on the present disclosure, thatadditional components and medical devices can advantageously be formedwith textured inner or outer surfaces to minimize friction between suchsurfaces and adjacent surfaces during use. Thus, the various embodimentsthereof are not limited to those specifically shown and describedherein.

Various modifications and additions can be made to the exemplaryembodiments discussed without departing from the scope of the presentinvention. For example, while the embodiments described above refer toparticular features, the scope of this invention also includesembodiments having different combinations of features and embodimentsthat do not include all of the above described features.

1. A guide catheter for guiding a medical device into or through a body lumen, comprising: a polymeric, tubular liner having a textured inner surface defined by a plurality protrusions disposed about and extending radially inward with respect to a longitudinal axis of the tubular liner, the tubular inner liner defining a catheter lumen; and a polymeric jacket bonded to an exterior of the tubular liner.
 2. The guide catheter of claim 1, wherein the protrusions are shaped to minimize contact area and frictional resistance between the textured inner surface of the tubular liner and the medical device when the medical device is disposed within the catheter lumen.
 3. The guide catheter of claim 2, wherein the protrusions extend longitudinally along the tubular liner.
 4. The guide catheter of claim 2, wherein the protrusions extend in a helical pattern longitudinally along the tubular liner.
 5. The guide catheter of claim 1, wherein the tubular liner comprises an extruded tubular member formed of a polymeric material.
 6. The guide catheter of claim 1, wherein the tubular liner comprises a molded tubular member formed of a polymeric material.
 7. A medical system comprising: an elongate medical device including an outer surface; a catheter having a lumen sized to receive the elongate medical device, the lumen including an inner surface; wherein one of the outer surface of the elongate medical device and the inner surface of the guide catheter lumen is a textured surface, and wherein the other of the outer surface of the elongate medical device and the inner surface of the guide catheter lumen is a substantially smooth surface, such that the textured surface is configured to minimize friction between the textured surface and substantially smooth surface when the elongate medical device and the catheter are moved relative to one another when the elongate medical device is disposed within the catheter lumen.
 8. The medical system of claim 7, wherein the textured surface includes a plurality of raised surface features.
 9. The medical system of claim 7, wherein the plurality of raised surface features extend longitudinally along the textured surface.
 10. The medical system of claim 7, wherein the plurality of raised surface features extend in a helical pattern longitudinally along the textured surface.
 11. The medical system of claim 7, wherein the elongate medical device comprises an extruded tubular member formed of a polymeric material.
 12. The medical system of claim 7, wherein the elongate medical device comprises a molded tubular member formed of a polymeric material.
 13. The medical system of claim 7, wherein the elongate medical device is a guide wire.
 14. A method of forming a guide catheter for guiding a medical device into or through a body lumen, the method comprising: forming a guide catheter shaft including an inner lumen sized to receive the medical device therein, the inner lumen including a textured inner surface along at least a portion of a longitudinal length of the catheter shaft, wherein the textured inner surface is configured to minimize friction between the textured inner surface and the medical device when the medical devices disposed within the catheter lumen.
 15. The method of claim 14, wherein forming the guide catheter shaft includes: forming a liner having a surface texture on an inner surface thereof; and disposing an outer jacket over the liner, wherein the inner surface of the liner defines the textured inner surface of the inner lumen of the catheter shaft.
 16. The method of claim 15, wherein forming the liner includes extruding a tubular polymeric member over an extrusion core having a surface configured to form the surface texture on the inner surface of the liner.
 17. The method of claim 14, wherein forming the guide catheter shaft includes: providing a polymeric jacket; extruding an liner over an extrusion core having a surface configured to form a texture on an inner surface of the liner; bonding the polymeric jacket to an exterior of the liner; and removing the extrusion core, whereupon such removal the inner surface of the liner defines the textured inner surface of the inner lumen of the catheter shaft.
 18. The method of claim 14, wherein the textured inner surface includes a plurality of raised surface features.
 19. The method of claim 18, wherein the plurality of raised surface features extend longitudinally along the liner.
 20. The method of claim 18, wherein the plurality of raised surface features extend in a helical pattern longitudinally along the liner. 